1. Field of the Invention
The present invention relates to telecommunications and, more particularly, to methods and systems for forward link and/or reverse link power control that use variable power control parameters.
2. Description of Related Art
Wireless telecommunications networks often use procedures for controlling the transmit power of forward link signals (i.e., signals transmitted from the network to a mobile station) and/or the transmit power of reverse link signals (i.e., signals transmitted from a mobile station to the network). For example, code division multiple access (CDMA) networks may use an “inner loop” process and an “outer loop” process for controlling the transmit power of forward link and/or reverse link signals.
In a conventional “inner loop” process, a receiving device receives a wireless signal transmitted by a transmitting device. The receiving device periodically assesses the strength of the received signal, such as by determining the signal-to-noise ratio (SNR), and compares the observed value to a setpoint. If the observed value is lower than the setpoint, the receiving device instructs the transmitting device to increase the transmit power of the wireless signal. If the observed value is higher than the setpoint, the receiving device instructs the transmitting device to lower the transmit power of the wireless signal.
In a conventional “outer loop” process, the receiving device periodically determines an error level in the received signal. The receiving device may then adjust the setpoint used for power control based on the observed error level. For example, if the error level is too high, the receiving device may increase the setpoint, which may lead to a corresponding increase in the transmit power level, via the “inner loop” process.
In this way, the “inner loop” and “outer loop” process may be used to adjust the transmit power level to maintained a desired signal quality despite changing conditions.